The present invention relates to a foam fire-extinguishing composition. More particularly, it relates to a foam fire-extinguishing composition comprising a water-soluble high molecular compound having a fluoroalkyl group and a water-solubilizable group.
It is known that the addition of a fluorine-containing surfactant to a conventional foam fire-extinguishing agent such as a synthetic surfactant containing no fluorine atom or a hydrolyzed protein-containing foaming agent improves and enhances the fire-extinguishing performances of the latter [cf. Japanese Patent Publication (examined) Nos. 20080/1965, 21078/1972, 26106/1972 and 35239/1977; Japanese Patent Publication (unexamined) No. 29689/1973, etc.]. For instance, a fire-extinguishing composition comprising them can form a thin, aqueous film on the surface of an inflammable liquid to prevent the diffusion of the vapor of the inflammable liquid and inhibit the reignition of the inflammable liquid once extinguished. Further, for instance, the said fire-extinguishing composition can enhance the physical properties such as heat resistance of the foams resulting therefrom. However, such fire-extinguishing composition is not effective in enhancement of the fire-extinguishing performances against the firing due to polar organic solvents such as acetone and ethanol.
As fire-extinguishing agents for polar organic solvents, there are known (1) a composition comprising a hydrolyzed protein and a metal soap dissolved in an amino alcohol, (2) a composition comprising a synthetic surfactant and a metal soap, (3) a composition comprising a synthetic surfactant and a water-soluble high molecular compound such as sodium alginate, etc. However, the composition (1) is required to be used quickly after mixing with water. Further, such composition produces precipitates on storage. The compositions (2) and (3) hardly produce precipitates but, because of using a synthetic surfactant as a main component, liquid resistance is greatly inferior.